Electric welding



T. E. MURRAY, JR.

ELECTRIC WELDING.

APPLICATION FILED MM2, I9I9.

Patented Mar. 9,1920.

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u I I I f n n J L 3W? my j@ 3 ma mm am we THOMAS E. MURRAY, JR., 0F BROOKLYN, NEW YORK.

ELECTRIC WELDING.

Application led May 2, 1919. Serial No. 294,299.

To all whom t may concern Be it known that I, THOMAS E. MURRAY, Jr., a citizen of the United States, residing at Brooklyn, in the county of Kings and State of New York, have invented a certain new and useful Improvement in Electric Welding, of which the following is ay specification. Y

The invention relates to electric welding', and consists in an apparatus for the equalization or variation, as may be desired, of the current distribution at the joint, said apparatus beinfr a specific embodiment of the invention Froadly claimed in U. S. Letters Patent No. 1,320,894, granted to me November 4th, 1919. The invention consists in the construction more particularly set forth in the claims.

In the accompanying drawings- Figure 1 is a transverse section on the line 1, 1 of F ig.,2, the upper movable electrode being shown partly broken away and its operating mechanism being omitted. Fig. 2 is a plan view of the transformer, and Fig. 3 is a perspective view of the primary coils and core of said transformer the secondary being omitted and the circuit connections leading to the source of welding current being shown. Fig. 4 is a perspectiveview of the work before welding.

Similar letters of reference indicate like parts.

A is the upper welding electrode, which is to be provided with any suitable mechanism for moving it toward and from the lower fixed electrode B. In said electrodes are registering semicircular recesses, in which respectively are seated the two objects to be weldedthe said objects being here two longitudinal half sections C, D of a T-shaped pipe, shown in perspective in F ig. 3.

E, F, G, H, I, J, K are primary transformer coils. The coils E, F, G are received upon the straight core member L, the coils H, I upon the right angled core member M, and the coils J, K upon the right angled core member N. The core members M, N are connected to one another by a removable end bar O and to the core member L by removable end bars P.

The united core members with the primary coils in place are seated in a metal T-shaped box Q which has a middle T- shaped rib R with a flat upper surface. The

Specification of Letters Patent.

Patented Mar. 9, 1920..

walls of the box are turned over at their upper edges, as shown at S. The lower electrode B is seated upon the rib R, and the upper electrode A is electrically connected to walls S by flexible wires T. The several primary coils are connected in branch to the leads U, V. In each branch is a switch W, sc that any single primary coil, or group cf coils, can be cut out of or brought into circuit with the source of current supply.

Because of the disposition of the primary coils (here all alike) upon the frame shaped core, the welding current, when all the switches W are closed, is distributed equally to each of said coils, and the said coils being spaced apart on the core at substantially like intervals, induce a uniform welding current throughout the rib B, which in turn passes to the electrode B in contact with said rib, and so to the joint between the half sections C, D. l

In assembling the parts, the primary coils are wound or slipped upon the members M, N and L of the T-shaped core, after :which the end bars O, P are secured 1n place.

The number of primary coils and their position on the core can, of course, be modilled to suit particular conditions of current distribution. In the present instance, I have applied two coils K, G-E, H-and I, J at the ends of each arm of the T, and an additional coil F in the middle of the member L, in order to equalize said current distribution; but if, for any reason, it seemed desirable to concentrate the heating etfoctfupon some definite localized area of the joint, I might provide the apparatus with only the particular coils acting upon said area and omit all others instead of providing all of the coilsv shown and cutting some of them out of circuit by means of their associated switches W.

I claim:

1. An apparatus for electric welding, comprising a frame shaped core, a plurality of primary coils thereon, a box-shaped secondary, a correspondingly shaped rib therein inclosed by said core and forming one ter mina] of said secondary, a fixed electrode in contact with said rib, and a cooperating movable electrode connected to the opposite terminal of said secondary.

2. An apparatus for electric welding, as

n claim l, further including means for inand removable end bars P connecting said dependently energizing each of said primembers M, N to-sad member L. 10 mary coils. In testimony whereof I have alxed my 3. An apparatus for electric Welding, as signature in presence of two Witnesses. 5 in claim l, the said frame shaped core con- THOMAS E. MURRAY, JR.

sistng of two right angled members M, N, Vftnosses: a straight member L, a removable end bar GERTRUDE T. PORTER,

O connecting together said members M, N, MAY T. MCGARRY., 

